refactor(posts): use precise cache invalidation in create/update/delete

src/api/posts/create.rs

@@ -139,17 +139,14 @@ pub async fn create_post(
 
         tx.commit().await.map_err(AppError::tx)?;
 
-        // 写入成功后失效文章列表、标签与统计缓存。
+        // 写入成功后按粒度失效相关缓存。
         crate::cache::invalidate_post_lists();
         crate::cache::invalidate_all_tags();
         crate::cache::invalidate_post_stats();
         // 失效按 slug 缓存，避免之前缓存的 404 继续命中。
         crate::cache::invalidate_post_by_slug(&final_slug).await;
-
-        // 失效该文章涉及的所有标签缓存。
-        for tag_name in &tags_cleaned {
-            crate::cache::invalidate_posts_by_tag(tag_name).await;
-        }
+        // 失效该文章涉及的所有标签下文章列表缓存。
+        crate::cache::invalidate_tag_posts_for(&tags_cleaned).await;
 
         Ok(CreatePostResponse {
             success: true,

src/api/posts/delete.rs

@@ -27,6 +27,34 @@ pub async fn delete_post(post_id: i32) -> Result<CreatePostResponse, ServerFnErr
     {
         let client = get_conn().await.map_err(AppError::db_conn)?;
 
+        // 在软删除前查询 slug 与标签，用于后续精准失效缓存。
+        let slug_row = client
+            .query_opt(
+                "SELECT slug FROM posts WHERE id = $1 AND deleted_at IS NULL",
+                &[&post_id],
+            )
+            .await
+            .map_err(AppError::query)?;
+
+        let Some(slug_row) = slug_row else {
+            return Ok(CreatePostResponse {
+                success: false,
+                message: "文章不存在".to_string(),
+                post_id: None,
+                slug: None,
+            });
+        };
+        let slug: String = slug_row.get(0);
+
+        let tag_rows = client
+            .query(
+                "SELECT t.name FROM tags t JOIN post_tags pt ON t.id = pt.tag_id WHERE pt.post_id = $1",
+                &[&post_id],
+            )
+            .await
+            .map_err(AppError::query)?;
+        let tags: Vec<String> = tag_rows.iter().map(|r| r.get(0)).collect();
+
         // 软删除：仅影响未被删除的文章。
         let result = client
             .execute(
@@ -45,14 +73,18 @@ pub async fn delete_post(post_id: i32) -> Result<CreatePostResponse, ServerFnErr
             });
         }
 
-        // 删除后所有文章相关缓存均失效。
-        crate::cache::invalidate_all_post_caches();
+        // 删除后按影响范围精准失效缓存。
+        crate::cache::invalidate_post_lists();
+        crate::cache::invalidate_all_tags();
+        crate::cache::invalidate_post_stats();
+        crate::cache::invalidate_post_by_slug(&slug).await;
+        crate::cache::invalidate_tag_posts_for(&tags).await;
 
         Ok(CreatePostResponse {
             success: true,
             message: "删除成功".to_string(),
             post_id: Some(post_id),
-            slug: None,
+            slug: Some(slug),
         })
     }
 

src/api/posts/update.rs

@@ -198,17 +198,17 @@ pub async fn update_post(
         // 失效文章列表、标签、当前 slug 与统计缓存。
         crate::cache::invalidate_post_lists();
         crate::cache::invalidate_all_tags();
-        crate::cache::invalidate_post_by_slug(&final_slug).await;
         crate::cache::invalidate_post_stats();
+        crate::cache::invalidate_post_by_slug(&final_slug).await;
 
         // 合并旧标签与新标签，统一失效标签下的文章列表缓存。
-        let all_tags_to_invalidate: std::collections::HashSet<String> = old_tags
+        let all_tags_to_invalidate: Vec<String> = old_tags
             .into_iter()
             .chain(tags_for_invalidation.into_iter())
+            .collect::<std::collections::HashSet<_>>()
+            .into_iter()
             .collect();
-        for tag_name in &all_tags_to_invalidate {
-            crate::cache::invalidate_posts_by_tag(tag_name).await;
-        }
+        crate::cache::invalidate_tag_posts_for(&all_tags_to_invalidate).await;
 
         // 若 slug 发生变更，额外失效旧 slug 缓存。
         if let Some(ref old) = old_slug {